Adjustable flue-bottom



Nb. 10,897. PATENTED MAY g, 1354.

A. M. SPRAGUE. ADJUSTABLE FLUE BOTTOM OF STEAM BOILERS scribed andrepresented in the following SPGClfiCEItlOIlS and drawings.

' purpose.

' N fitted to turn in appropriate bearings in ALEXANDER M. sPRAGUE, orMOBVILE. ALABAMA.

ADJUSTABLE FLUE-BOTTOM 0F STEAM-BOILERS.

Specification of Iiette'rs Patent No. 10,897, dated May 9, 1854.

To all whom it ma y concern Be it known that I, ALEXANDER M.

SPRAGUE, of the cityand county of Mobile,

in the State of Alabama, have invented certain new and usefulImprovements in the Flues of Furnaces for Steam-Boilers; and I doherebydeclare that the same are de- To enable others skilled in the artto make and use my improvements I will proceed todescribe theirconstruction and .use, referring to the drawings, in whichthe sameletters indicate like parts in each of the figures.

Figure l, is an elevation of a furnace and boilers. Fig. 2, is anelevation with the side of the furnace omitted to show the interior.Fig. 3, is an elevation of one end.

The adjustable bottom M may be made in the form represented or in suchother form as may be desirable, and fitted to the space in the furnaceunder the boiler or boilers and beyond the grate, and perforated for thestandards I and J. J, and arranged so as to be raised and lowered withfacility by such apparatus as may be provided for that There are twoormore shafts N the sides of the furnace, and of sufficient length toextend through one side and allow the ends of the arms 0, O, to befastened upon them, as represented, each of which arms is provided witha pivot P, P, to

' which the bar. Q is fitted, so as to operate all the rock shafts N Nat the same time. To operate these rook shafts a rack R is provided andfitted to traverse in the bracket S, fastened to the side of thefurnace, when it is acted upon by the pinion T, upon the shaft U, fittedto turn in the bracket S and the side of the furnace, and is operated bythe hand winch or lever V. Each of the shafts N N is provided with twoarms, such as are represented at W W, which arms carry the supports XX,'connected to them as represented, which supports extend up intoscores in the brackets Y Y fastened tothe adjustable bottom M, so as toraise and lower it as the shafts N N are turned by traversing the rackR, as above described, which rack may be retained in the desiredpositionby inserting a pin in'one of the holes, as shown at a.

The adjustable bottom M should be made to correspond or nearly so withthe bottom of the boiler or boilers as represented in represented. orotherwise.

F ig.- 3, and the end toward the grate may be made straight across andbent up, as represented at K, Fig. 2, so that the upper end of theinclined vibrating piece or bridge may be further secured by the links6, as j The lower end of the piece Z rests and traverses upon the bottomof the furnace just beyond the grate as the bottom M is raised orlowered, as

above described, to adjust the space between the bottom M and theboilers to suit the kind of fuel being burned in the furnace.

back end of the furnace f and is bent at right angles and passes througha hole in the plate d and the slot in the bottom M,

so that the plate cZmay be pulled against the wall, so as to close thespace by drawing the rod 6 when necessary. The bottom M and the plate Zmay be covered with a layer of fire or other brick.

It is apparent from the foregoing description that myimprovements enablethe engineer to vary the space or fine under the boiler through whichthe flame passes and adapt it to the state of his fire or the kind offuel he is burning, whenever he pleases, by turning the shaft U, asheretofore described, for if the fuel which he is consuming produces alarge volume of flame a large space under the boilers will be requiredfor its escape; but if the fuel is inferior and produces but a smallvolume of flame he can reduce the space under the boiler by raising themovable bottom and adapt it to the volume of flame produced, so as togenerate the most steam possible by the fuel consumed,

60 Z, may hook onto it, asrepresented, and it permanent bottom C, sothat they can be raised bythe engineer, so as to compel the flame topass close to and in contact with the boiler as it passes over each ofthese gates in succession. The tops of these gates may be made tocorrespond, or nearly so, with the bottom of the boiler, and they may bemade of soap-stone or fire-brick or of iron faced with soap-stone orfire-brick or of such other material as willanswer the purpose.

My improvements are peculiarly and par- 'ticularly adapted to and forthe boats navigating the long rivers on the American continent, wherethe kind of fuel is changed several times a day or once in a few hours,for a boat at New Orleans may have a sup ply of fat pine wood and as sheascendsthe Mississippi river she may get the following kinds of wood andcoal: Cotton-wood, hackberry, ash, oak, beech, and bituminous coal.Besides the wood may be either dry or seasoned or fresh out and green,so that there may be a great loss in burning it without my improvementsabove described.

What I claim as my invention and desire to secure by Letters Patent, is

l. The movable adjustable bottom of the flue space under the boiler orboilers, so constructed and arranged that it may be raised and loweredor adjusted to graduate the size of the flue under the boiler or boilersthe inclinedvibrating piece or bridge Z or its equivalent so constructedand arranged that it will operate with the bottom M and conduct theflame from the furnace into the flue under the boilers substantially asde- Witnesses: 1

. J. DENNIS, Jr.,

SAML. A. ARNOLD, SAML. GRUBB.

